在http://www.prtools.org/download.html网页中注册下载academic版本Matlab的PRtools模式识别工具箱，

但是运行dd_tools中的oc_set函数会引用PRtools中的prtver函数，运行会出错！

我下载下来的prtools_ac.zip中代码修改日期为2011.10.11，根据2011.04.04版本的代码直接修改prtver.m一点点即可！

%PRTVER Get PRTools version
%
%This routine is intended for internal use in PRTools only

function prtversion = prtver

persistent PRTVERSION
if ~isempty (PRTVERSION)
	prtversion = PRTVERSION;
	return
end

verstring = version;
if strcmp(computer,'MAC2') | verstring(1) == '5';
%	name = fileparts(which('fisherc'))
%	[pp,name,ext] = fileparts(name(1:end-1))
	ver_struct.Name = 'Pattern Recognition Tools';
	ver_struct.Version = '4.0.0';
	ver_struct.Release = '';
	ver_struct.Date = '';
	prtversion = {ver_struct datestr(now)};
else
% 	[pp,name,ext] =fileparts(fileparts(which('fisherc')));
% 	vers = ver([name,ext]);
% 	if isempty(vers)
% 		vers = 0;
%  		error([newline 'This version of PRTools is not properly defined as a toolbox.' ...
%  		newline 'Please add it first, e.g. using the addpath command with the path from root!'])
% 	end
% 	prtversion = {ver([name,ext]) datestr(now)};
	prtversion = {ver('prtools') datestr(now)};
end
PRTVERSION = prtversion;

prtversion = {ver('prtools') datestr(now)};

但是奇怪的是，当运行成功后，我再次把原始2011.10.11的prtools_ac.zip放到toolsbox中居然不会运行出错！！

这是奇怪！